#!/usr/bin/perl -w

## ======================== ##
## Author:                  ##
## Email:                   ##
## Date:    13.11.2012      ##
## Version: 1.0             ##
## ======================== ##

## Info:

use strict;
use warnings;
use File::Basename;
use Getopt::Long;
use LWP;
use Data::Dumper;
use XML::LibXML;

use vars qw(
        $opt_hostname
        $opt_query_url
        $opt_basic_user
        $opt_basic_pass
        $opt_timeout
        $opt_verbose
        $opt_help
);

my $progname = basename($0);
my %ERRORS = ('UNKNOWN'  => '3',
              'OK'       => '0',
              'WARNING'  => '1',
              'CRITICAL' => '2');

sub print_help();
sub get_xml_value;

my $opt_servicename = "HOST";
my $opt_basic_realm = "Notify XML Kerberos Access";

Getopt::Long::Configure('bundling');
GetOptions(
        "H=s" => \$opt_hostname, "hostname=s" => \$opt_hostname,
        "S=s" => \$opt_servicename, "servicename=s" => \$opt_servicename,
        "U=s" => \$opt_query_url, "query-url=s" => \$opt_query_url,
        "u=s" => \$opt_basic_user, "basic-user=s" => \$opt_basic_user,
        "p=s" => \$opt_basic_pass, "basic-pass=s" => \$opt_basic_pass,
        "r=s" => \$opt_basic_realm, "basic-realm=s" => \$opt_basic_realm,
        "v" => \$opt_verbose, "verbose" => \$opt_verbose,
        "t=s" => \$opt_timeout, "timeout=s" => \$opt_timeout,
        "h" => \$opt_help, "help" => \$opt_help
) || die "Try `$progname --help' for more information.\n";

local $SIG{ALRM} = sub{
        print "Timeout after $opt_timeout seconds";
        exit $ERRORS{'UNKNOWN'};
};

if($opt_timeout){alarm($opt_timeout);}

if(!$opt_help && $opt_hostname && $opt_query_url && $opt_basic_user && $opt_basic_pass){
        my $use_port = 80;
        my $base_url = "";
        my $query_url_regex = 'http([s]*):\/\/([\w-]+(\.[\w-]+|\.[\w-]+\.[\w-]+))\/.+/';
        if($opt_query_url =~ m/$query_url_regex/){
                if($1){$use_port = 443;}
                $base_url = $2;
        }
        else{
                print "ERROR - Unkonwn query url format: '$opt_query_url' != '$query_url_regex'\n";
                exit $ERRORS{'UNKNOWN'};
        }
        
        my $query_url = $opt_query_url.$opt_hostname."/".$opt_servicename.".xml";
        if($opt_verbose){print "Attempting to query url: $query_url - Base URL: $base_url\n";}

        my $user_agent = LWP::UserAgent->new;
        $user_agent->agent("Nagios/0.1");

        $user_agent->credentials(
                ($base_url.":".$use_port),
                $opt_basic_realm,
                $opt_basic_user => $opt_basic_pass
        );

        my $request = HTTP::Request->new(POST => $query_url);
        $request->content_type('text/plain');
        $request->content('query=libwww-perl&mode=dist');

        my $response = $user_agent->request($request);
        if(!$response->is_success){
                print $response->status_line."\n";
                if($opt_verbose){"Dumping user agent:\n".Dumper($user_agent)."Dumping response:\n".Dumper($response);}
                exit $ERRORS{'UNKNOWN'};
        }
        if($opt_verbose){print $response->content."\n";}
        my $document = XML::LibXML->new->parse_string($response->content);
        my $check_type = "HOST";
        if($opt_servicename){$check_type = "SERVICE";}
        my $nagios_perfdata = get_xml_value($document,"NAGIOS_".$check_type."PERFDATA");
        if($nagios_perfdata){$nagios_perfdata = "|$nagios_perfdata";}
        my $output = get_xml_value($document,"NAGIOS_".$check_type."OUTPUT").get_xml_value($document,"NAGIOS_LONG".$check_type."OUTPUT");.$nagios_perfdata;
        $output =~ s/\\n/\n/g;
        print $output;
        exit get_xml_value($document,"NAGIOS_".$check_type."STATEID");
}
else{print print_help();exit $ERRORS{'UNKNOWN'};}

sub get_xml_value{
        my ($document,$value) = @_;
        my $returnvalue = "";
        for($document->findnodes("//status/$value/text()")){$returnvalue = $_->toString();}
        return $returnvalue;
}

sub print_help () {
        print "\n$progname - \n\n";
        print "Options are:\n";
        print "  -H, --hostname                  Nagios hostname\n";
        print "  -S, --servicename               Nagios servicename\n";
        print "  -U, --query-url                 The URL where xml files are found\n";
        print "  -u, --basic-user                Basic authentication user\n";
        print "  -p, --basic-pass                Basic authentication pass\n";
        print "  -r, --basic-realm               Basic authentication realm\n";
        print "  -v, --verbose                   verbose output - not for Nagios\n";
        print "  -t, --timeout                   timeout in seconds\n";
        print "  -h, --help                      display this help and exit\n\n";
        print "Example:\n";
        print "  ./$progname\n\n";
}

print "End of script. Should not be reached\n";
exit $ERRORS{'UNKNOWN'};